Two gang members have been charged with first-degree murder for the killing of Hadiya Pendleton in a South Side Chicago park.

Michael Ward, 18, and Kenneth Williams, 20, opened fire on Pendleton and a group of other students, mistaking them as rival gang members who shot and injured one of them over the summer.

Ward and Williams were arrested Saturday night on their way to a strip club, only hours after the 15-year-old's funeral, which First Lady Michelle Obama attended. Hadiya's parents, Nathaniel Pendleton and Cleopatra Cowley-Pendleton, will be guests of President Obama at the State of the Union address tonight.

Hadiya's father, Nathaniel Pendleton, said Monday night that news of the charges marked the first time since his daughter's slaying that he had a "legitimate" smile on his face.

"I'm ecstatic that they found the two guys," he told the Tribune during a brief telephone interview from Washington, D.C., where he and wife Cleopatra Cowley-Pendleton will attend the State of the Union address Tuesday as guests of President Barack Obama. "(I'm) thanking God that these two guys are off the streets, so that this doesn't happen to another innocent person."

Danetria Hutson, 15, who held Hadiya in her arms after she was shot, said she and others in the group have had nightmares since the shooting.

In addition to waking up in the middle of the night, Hutson, also a sophomore at King, said she and others in that group also haven't been able to bring themselves to hang out at parks since that day.